Cream of Tartar

potassium bitartrate or potassium hydrogen tartrate

Cream of tartar is a by-product of winemaking. It crystallizes out of wine during the fermenting process and may also crystallize out of cold grape juice. These raw potassium bitartrate crystals are called "beeswing".

Sometimes these crystals can be found under the cork when you open a bottle of wine that has been stored in a cool place. These are called "wine diamonds".

Crystals can also form on homemade jams and jellies and you may find these unattractive. To prevent this, chill the grape juice you are going to use overnight and then filter any crystals through a cheesecloth and use the filtered juice.

Archaeologists can use the presence of tartaric acid crystals in the bottom of ancient jars to help them make conclusions about the history of wine making.

Cream of Tartar is a white, odorless, acidic powder. It was first isolated by the Persian alchemist Jabir ibn Hayyan in during the 7th century CE. Alchemists use "salt of tartar" and "oil of tartar", both made from tartaric acid for a variety of things.

Cream of tartar is generally used as a food stabilizer. It can be added to whipped cream to keep it fluffy and to egg whites before beating to lower the ph and help encourage peaks to form as when making meringue. Adding cream of tartar to sugar solutions, like frosting and glazes, prevents them from crystallizing and helps maintain a smooth, glossy finish.

Adding a tiny amount of cream of tartar to boiling vegetables can help prevent loss of color without affecting the taste.

Cream of tartar is also occasionally added to baking powder and salt substitutes for those on low sodium diets.

Cream of tartar is also an important ingredient in cleaning solutions to fight hard water stains and to clean metal cookware. Just mix with vinegar to make a paste and scrub it on the offending stains. Because cream of tartar is acidic, it won't fizz like baking soda when combined with vinegar.

A combination of cream of tartar and hydrogen peroxide can be used to remove rust.

Cream of tartar can be used as a mordant for some natural dyes.

Cream of tartar is very rich in potassium. It should be used with caution by people with kidney problems and people who suffer from chronic pain.

Large amounts of cream of tartar are toxic and can cause violent illness and death.